Mechanism for feeding sheet-metal blanks and the like



Oct. 30, 1928.

E. V. SWANGREN MECHANISM FOR FEEDING SHEET METAL BLANKS AND THE LIKEFiled Nov. 10, 1923 6 Sheets-Sheet 1 MW @www mw 1mi @y WM Oct. 30, 1928.

E. V. SWANGREN MECHANISM FOR FEEDING SHEET METAL BLANKS AND THE LIKE 6Sheets-Sheet 2 am; m1@

Filed Nov. 10, 1923 Cet. 30, 1928. 1,689,756

E. v. swmuGRl-:Nv

MECHANISM FOR FEEDING SHEET METAL BLANKS AND THE LIKE l Filed Nov. 10,1923 6 Sheets-Sheet 3 Wthes l Oct. 30, 1928.

E. V. SWANGREN MECHANISM FOR FEEDING SHEET METAL BLANKS AND THE LIKEFiledxNovn. 1o, 192s 6 Sheets-sheet 4 Oct. 30, 1928. 1,689,756

i V. SWANGREN MECHANISM FOR FEEDING SHEET METAL BLANKS AND THE LIKEFiled Nov. 1o, -1923 6 Sheets-Sheet 5 IIIII *Zi m W f2 jfzvmzof Weis@117W Mmm/1MM @y 45%, M1 in 75' Oct. 30, 1928. 1,689,756

E. v. SWANGREN y MECHANISM FOR FEEDING SHEET/METAL BLANxs AND Tm; LIKEFiled No\ r.1o, 1925 6 Sheets-sheet e Patented Oct. 30, 19928.

UNITED STATES PATENT OFFICE.

EDWIN V. SWANGEN, F MAYWOOD, ILLINOIS, ASVSIGNOR OF ONE-HALF T0 WILLIAIM. STEVENSON, 0F EVANSTON, ILLINOIS.

MECHANISM FOR FEEDING SHEET-METAL BLANKS AND THE LIKE.

Application led November 10, 1928. Serial No. 674,099.

l My invention relates to a machine which is designed to feed flatsheetmetal blanks one by one from a stack of sheet metal blanks tomechanisms for performing further operations on the blank. In thepresent instance the feeding and delivering mechanisms which form theprincipal features of my invention are associated with a stampingmechanism arranged to stamp and form blanks passing through the machine,and which cooperates synchronously with the feeding and deliverymechanism, in the manufacture of articles from the blanks operated upon.One important feature of my invention is the provision of a novelfeeding mechanism by means of which the lowermost blanks of the stackare successively withdrawn and delivered through transfer mechanism tothe stamping mechanism; another relates to the provision of novelmechanism for transferring and delivering the formed blanks; another tothe provisions made for adjustment of groups of mechanisms unitarily;and still others relate to various provisions made in the constructionand arrangement of parts, and to various combinations andsub-combinations of associated and cooperating elements which I havedevised for the purpose of adapting and perfecting the machine toefficiently perform the functions for which it was designed. In theappended claims I have more particularly pointed out the essentialfeatures of my invention, it being understood however, that variousmodifications of construction within the scope of the claims arepossible, without departing from the true spirit and substance of myinvention.

In the drawings I have illustrated a ma.- chine which embodies myinvention in a dcsirable and preferred form, for the purposes ofexposition and explanation, though variations in the form andarrangement of structural members and detail of construction will-readily occur to those skilled in the art.

Figure 1 of the drawings is a plan view of the machine; Fig. 2 is a leftside elevation of the same, the end of the machine at the right in saidfigure being regarded as the front end Fig. 3 is an elevation of thefront end of the machine; Fig. 4 is a central vertical section, viewedfrom the left side; Figs. 5, 6 and 7 are similar vertical cross-sectionson the line 5--5 of Fig. 2, some of the parts being shown anism; Fig. 8is a face view of a cam for imparting movement to parts of the feedingmechanism; Figs. 9 and 10 are detail sections at right angles to eachother and passing centrally through the left hand one of a pair ofsuction cups employed in the feeding mechanism, Fig. 9 illustrating theposition of the parts as viewed from the front end of the machinead Fig.10 as viewed from the left side Fig. l1 is an enlarged verticallongitudinal section of a portion of one of the pair of reciprocatingfeed bars, on the line 11-11 of Fig. l; Figs. 12 and 12l1 arefragmentary transverse sections through the front and rear pressure barsupports on the dotted lines 12--12 and 12a-12, respectively, of Fig. 1;Fig. 13 is a central longitudinal vertical section of the rear portionof the machine, portions of the mechanism being shown in elevation; andFig. 14 is a det-ail showing in perspective one of the sliding blocksand its associated oscillating finger for delivering the formed articleafter the stamping mechanism has operated upon the blank.

The same reference characters indicate the Same parts on all the figuresof the drawi The stationary supporting frame of life machine may beconstructed in any desired manner so that it will afford suitablesupport to the other parts. In the machine illustrated the main frameconsists ofa lcasting 1 supported on legs 2, and formedw'ith sidemembers 3, a front cross member 4, a rear cross member 5 and anintermediate strengthening member 6. To provide for adjustment of themachine to operate upon blanks of different sizes, the moving parts andassociated elements of the feeding mechanism, which consists of pairs ofoppositely arranged symmetrical members are mounted upon oppositesymmetrical side beams 7-7 which are slidably mounted in the machineframe so that they may 'be adjusted simultaneously towards and awa fromthe median line of the machine. To tis end the beams are formed withfront base blocks 8 and rear base blocks 8a having dove-tailed recessesarranged to slidingly engage transverse guide rails 9 formed on thestationary frame of the machine. The side beams are also formed withfront and rear internally threaded bosses arranged to respectivelyengage the opposite portions of a front right-and-left threadedadjusting screw 10, and a similar rear screw 10. The two screws have aswivel connecv machine from the feeding to the forming and deliverymechanism, and in the top faces are "formed guideways to receivereciprocating feed bars 11-11 by means of which the blanks areintermittently carried rearward, as hereinafter explained. .f

The supporting structure of the sheetholding and feeding mechanismincludes, in the present instance, a front corner block 12 and a rearcorner block 13 rigidly secured to the outer face of each side beamadjacent its front end and a frame bar 14 extending lon- 'tudinally ofthe machine and secured to the top of the two corner blocks. Uponeachbar 14 is mounted a pair of similar oppositely arranged brackets 15 towhich are secured vertical spacing posts 16. The brackets are secured tothe bars by means of bolts 17, which engage any one of a series ofthreaded seats in the bars, the orifices in the base flanges of thebrackets being elongated sufficiently to permit adjustment of thebrackets` at any point between the seats. The posts 16 may thus beadjusted to receive a stack of blanks of any desired width from front torear of the machine.

Midway between the brackets 15 a side spacing post isv secured to theinner face of each frame bar 14, the two posts 18 serving to confine thestack of blanks to a central portion in the machine.

The stack of blanks confined by the posts 16 and 18 are maintained at afixed height a short distance above the top faces of the beam 7 by oneor the other of two alternately acting reciprocating devices, oneconsisting of a pair o vertically sliding supporting plates 19, and theother a pair of separating plates 20, mounted to have a lateraloscillating movement, the lowermost blank being withdrawn from ythestackand fed rearward during each cycle of movements of the parts, aswill now be explained in detail.

The supportingplates 19 are flat and rec-e tangular in shape, and aremounted to reciprocate vertically in shallow slideways cut in the outerfaces of the two side beams 7. On the outer side of each plate ismounted a cam roller 21 arranged to engagea cam,

groove formed in the inner side face of a rotating cam 22 which isjournaled in bear,- ings carried by the associated side beam 7,

` and which has splined connection with a cam shaft 23 through which itis driven and which is rotatably mounted in the side members of thestationary frame of the machine.

Each of the two separating plates 20 at opposite sides of the machine ispivoted at its outer corners to links 24 which are pivoted to lugs 12and 13=l extending outwardly from h the corner blocks 12 and 13respectively. Inwardly of the pivotal connection with the links, theplate 2O rides upon a pair of rollers 25 carried by the two cornerblocks. The plate is oscillated between the two positions sh wnrespectively in Figs. 5 and 6 by means of a rocking frame 26 pivotallymounted in bearings formed in the corner blocks 12 and 13 and havingupwardly extending side arms `26a connected by links 27 with the links24,

and having an intermediate inwardly extending arm 26b equipped with acam roller arranged to cooperate with. a cam groove formed in the outerface of the cam 22 before mentioned.

In the successive cycles of movement of the feeding mechanism theopposite side edges of the lowermost blank in the stack are drawndownwardly from the remaining sheets by means of a pair of suction cups27, one at each side of the machine,-see Figs. 5, 6, 7, 9 and 10.Thecups, which are formed of rubberor other suitable elastic materialare each mounted by means of a hollow screw 28 in a springpress slidingblock 29 mounted in a laterally extending arm 30 secured to a rock shaft31 journaled in bearings on the outer face of the associated supportingplate 19. This rock shaft is yieldingly stressed upwardly by a spring-32and has secured to it a downwardly extending arm 33 which engagesaperipheral groove 34 in the rotating cam 22. Since the suction cup androck shaft move in unison with the supporting plate the peripheral faceof the cam follows the contour of the cam groove engaged by the camroller 21, and the groove 34 follows this contour and has also an axialor lateral pitch which operates to produce a rising and falling movementof the suction cup with respect to the supporting slide as the partsrise and fall.

The block 29 is bored and provided with a tube connection to provide apassage between the interior of the cup and an exhaustexplained, itbeing understood that t e shape of the cams and setting of the cams andeccentric are such as bring about the movements in the order described.Immediately after the end of a rearward feeding movement of the blanksthrough the machine roduced by means which will later be descri ed),thevparts assume the position shown in Fig. 5,

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the stack of blanks, marked A, being supported by the plates 19; theseparating plates 20 in outermost position, and the suction cups raisedand just subjected to eXhaustlon to cause them to take hold of theopposite edges ofthe lowermost blank. The axial deviation of the path ofthe cam groove 34 now rocks the cup downward (the supportlng plates 19meanwhile remaining stationary) thus drawing down the edge of thelowermost blank, and closely following th1s movement the edges of theseparating plates 20 move inwardly under the lowermost blank to and pastthe position shown in Fig. 6, also moving slightly upwardly and comingto a dwell in the position shown in Fig. 7. The supporting plates 19immediately fall to lowermost position and the vacuum having at thispoint been relieved the edges of the blank spring up and it rests uponthe flush upper surfaces of the plates 19, the feed bars 11 and face ofthe side beams 7. As soon as the blank is fed rearwardly through arearward stroke of the feed bars and clears the rearward line of thestack of blanks the supporting plates move upwardly to uppermostposition, and the separating plates are immediately swung to outerposition and the suction cups then swing upwardly to the position shownin Fig. 5, to repeat the movements described in the next cycle.

Inasmuch as the suction cups are intercommunicating, if one cup shouldfail to adhere to the blank, because of an irregularity in the surfacesof the blank or a hole through it, the relief of the vacuum through suchcup would extend to the other cup, so that neither edge of the blankwould be drawn down, and the separating mechanism would operate idly,and not incorrectly, with consequent liability of damage to the machine,as would be the case were one side of the blank only acted upon.

The mechanism through which the blanks are intermittently movedrearwardly through the machine may next be described. In oppositedepending brackets forming part of the stationary frame of the mechanismis journaled a rock shaft to which is secured a rock arm 41 pivotallyconnected to one end of a connecting rod 42 which at its other end isthreaded to provide an adjustable connection with a pivot block 42awhich is pivoted to a cross-bar 44 passing through opposite slots in theside-beams 7 and engaging notches formed on the under sides of the feedbars 11. The crosshead structure is guided by a guide rod 47 whichslidingly engages a bushing arranged to be rigidly secured in a splitsocket 48 at the top of a supporting lbracket 49 secured to the crossbar4 at the frontend of the stationary frame of the machine.

Near the front end ofthe two feeding bars, the bars are equipped ontheir top side with opposite feed lugs or teeth 45, and rearwardlythereof, spaced the length of a feeding stroke apart, the top of thebar: carries springpressed ,feeding pawls 46 (see Fig. 11) which on theforward stroke of the bar yield to pass under a blank on the supportingupper face of the beams 7 and spring upwardly to engage the rear edge ofthe blank at the end of the stroke, and on the rearward stroke slide theblank rearwardly.

The blanks are held down upon the feed bars and upper faces of the sidebeams by means of pressure bars 47, which extend parallel with the feedbars a short distance outside of them on opposite sides of the machine.In the present instance (see Fig. l2) these pressure bars are providednear their front ends with inwardly-extending fingers 48 orificed. toeach loosely engage the stem of a screw 49 engaging a seat in anupturned marginal flange of the rear portion of the adjacent side beam.Interposed between the head of the screw is a spring 50 bearing on awasher 5l arranged on top of the finger, the tension of the bars beingregulated by adjustment of the screw. The rear ends of the pressure barsare also yieldingly mounted (see Fig. 12a) by means of verticallyspringpressed pins 49'L secured to the bars and mounted in brackets 48bbolted to the side beams 7 and of a curved form to provide clearance forparts to be hereinafter de# scribed.

Inasmuch as in stamping or forming machines as ordinarily constructedfor forming various kinds of pans and other articles having a flatbottom and upstanding sides, the bottom of the article to be formed froma blank rests upon a 'depressible spring-pressed plate which after thearticle is stamped automatically follows the forming die upwards,lifting the formed article so that its bot-tom comes to the planeoriginally occupied by the blank, and inasmuch as such movement of theannual spring-pressed plate would interfere with movements of the feedbars 11 of my machine, I have devised means for delaying the returnupward movement of the bottom plate so that it may operate insynchronism with the feed bars of the mechanism above described. To thisend the plate (marked 52) is equipped with a pair of depending verticalposts 53 which rest upon the top of a vertcally-reciprocating cross-head54 pivotally connected by a link 54 with the horizontal arm of abell-crank lever 55 fast upon a cross shaft 56 journaled in the frame ofthe mechanism. The vertical arm of the bell-crank is pivotally connectedwith the rear end of a connecting rod 57 which is formed with a slottedfront end arranged to engage a stud 58 upon a rock arm 59 secured to therock shaft 40 before mentioned, the arrangement of the parts being Suchthat during the closing portion of the rearward stroke of the rock armand stud the stud will contact the rear end of the slot and quicklyreturn the plate 52 to upper position.

The weight of t-he plate and connected parts is counterbalanced insuitable manner, as by the compression spring G0 surrounding one of theguide posts upon which the crosshead 54 is mounted to slide and a brake61 having one member also connected to the cross-shaft 56 is provided toyieldingly maintain the plate in the opposite portions to which it isshifted by application of the positive force of the press in thestamping operation and this action ofthe rock arm 59.

For the purpose of removing the formed articles from the machine at theconclusion of each stamping operation I employ a pair of rocking fingers62, mounted respectively on two sliding side of the machine and arrangedto engage stationary guide bars on the machine frame. Each finger has aneccentric pivotal connection with the rear end of a rod 64: which at itsfront end is pivoted to a bracket 65 secured to the feed bar 11 on thearticular side of the machine, and the inertia of the block 63 andfrictional resistance of the guide way in which Such block is mountedare such that the reciprocations of the feed bars will cause the fingersto oscillate from positions parallel with the bars to the transverseposition shown in Fig. 14 at the beginning of each rearward movementofthe feed bars, and return to their parallel positions at the beginningof each forward stroke, stops being provided for the lingers to bring upagainst at the limitl of each oscillation.

It will be understood that any suitable driving connections may beemployed for giving the described movements to the various parts. In thepresent instance a shaft which makes one complete rotation at eachcomplete toand-fro movement of the stamping mechanism is equipped with asprocket wheel (not shown) which through a sprocket chain 72 drives adouble sprocket wheel 73 rotatably mounted on` a stub shaft on thestationary frame of the machine. A second sprocket chain 74 engaging thewheel 73 engages a sprocket wheel 75 secured to the cam shaft.

23 before mentioned.

The operating shaft through which the parts just mentioned are actuatedalso has a crank connect-ion with the upper end of a connectin rod 7 6which is pivotally connected at lts lower end to a rock arm 77 fixed tothe rock shaft 40.

The arrangement of the parts is such that during each complete stampingoperation the blank-separating and blank-transferring mechanisms and theblank-removing mechax nism, each make one complete cycle of movements.The blank, separated from the stack in the manner already described, isdeposited on the top faces of the side beams 7 and feed blocks 63arranged one at each bars 11 as the latter reach-the forward end oftheir stroke. They are fed rearward in a given number of successivestrokes (three in the present instance), and at the end of the laststroke come to rest, centered in proper position, over the bottom plate52 of the stamping mechanism, which has just before been lifted to upperposition, the formed article which was left on the plate beingsimultaneously removed by the action of the slidingly mounted rockingfingers actuated by the feed bars. The feed bars and associated partsnow recede to forward position, and this movement isfollowed by thedescent. of the stamping die, the feeding fingers being ,oscillated toclear the die as the latter descends. Thesefeedingfingers,itmaybenoted,are of relatively fragile construction, so that in case of failure toshift to outer position for any reason, they, will readily crush and notcause damage tothe stamping mechanism.

Inasmuch as the center of the magazine for the blanks and the center ofthe stamping members are arranged a fixed number of strokes of thefeeding bars apart, it is only necessary to the yproper operation of themachine that the feed bars 11 be so adjusted in their ways that thefropt feed lugs 45 shall immediately engage the blanks separated fromthe stack in the magazine at the beginning of their rearward stroke.Thismay be accomplished by adjustment of the` connecting rod 42 in thepivot block 42'* of the crosshead structure to which the bars areconnected.

While for the purpose of exposition I have described my invention asembodied in a machine for stamping blanks formed of sheet metal, it willbe understood that by slight modification of parts to adapt it'to theparticular use, my invention may be adapted to machines operating onblanks of' other material than sheet metal. I therefore do not` desireto limit my invention to its employment for feeding 'sheet metal blanksonly.

It will further bev understood that my invention is not necessarilylimited to the particular construction of the mechanical elements andgroups of elements for performing the functions hereinbefore mentionedas these may vary widely in form and arrangement from the constructionherein described.

I therefore desire the claims to be construed to cover all equivalentparts or members or mechanisms which may be substituted for thoseparticularly described, or may be used to accomplish the same ends.

Iclaim:

1. In a machine for feeding sheet metal blanks and the like and havingintermittently acting means for supporting the central portion of astack of blanks and reciprocating means for intermittently drawing downmarginal portions of the bottom blank, separating means including amovable plate having an inward and upward reciprocating movementtransversely of the machine, said movable plate being pivotally mountedon rocking links and arranged to slide upon a stationary portion of themachine.

2. In a machine for feeding sheet-metal blanks and the like and havingintermittently acting means for supporting the central p ortion of astack of blanks and a reciprocating vacuum cup for intermittentlydrawing down a marginal portion of the bottom blank, separating meansincluding a plate having a reciprocating lateral movement, said platebe-` ing cut away to straddle the vacuum cup.

3. In a machine for feeding metal blanks and the like from a stack of blanks and having alternately acting supportingmeans for supporting, thecentral portion of the stack and separating means for supporting the Inarginal portion of the stack above a marginalseparated bottom sheet, areciprocating vacarranged to successively operate on marginal portionsof the bottom sheets of the stack, said vacuum cup beingslidinglymounted on a rocking arm.

4. A machine according to claim 3 in which said vacuum cup is carried bya springpressed block.

5. In a machine for feeding sheet-metal blanks and the like from a stackof blanks and having a vertically-reciprocating supporting member forintermittently supporting the central portion of the stack and havingalternatel acting separating means for supporting t e marginal portionof the stack above a marginally separated bottom sheet, a vacuum cupcarried by said supporting member and mounted thereon to have relativevertical movement with respect thereto.

6. A machine according to claim 5 in which said vacuum cup is mounted ona rocking arm pivoted on said supporting member.

7 A machine according to claim 5 and having a rotatin cam provided witha lateral radially-varying cam groove arranged to control the movementof said supporting member and with a peripheral cam groove varying bothradially a'nd axially arranged to control the movement of said vacuumcup.

8. A machine according to claim 5 in which said supporting member isslidingly mounted and equipped with a cam member and said vacuum cup ismounted on one arm of a bell crank pivoted on such supporting member andthe other arm is equipped with a cam member, and having a rotating camprovided with a rotating cam formed with a lateral cam groovecooperating with said rst mentioned cam member and a peripheral groovecooperating with said second mentioned cam member.

9. In a machine for feeding sheet-metal blanks and the like from a stackand having a vertically-reciprocatin supporting slide arranged tointermittently support the central portion of the stack, and having analtermately-acting separating late for supporting the marginal portion othe stack above a marginally-separated bottom sheet, and having a vacuumcup pivotally supported upon said supporting member and arranged tosuccessive y separate mar inal portions of the bottom sheets of the staca rotating cam provided with a lateral radially-varying cam groovearranged to control the movement of said supporting member and also witha cam groove varying both radially and axially arranged to control themovement of said vacuum cup and also with a lateral radially-varying camgroove arranged to control the movementof said separating plate.

10. A machine according to claim 9 in which said supporting slide isequipped with a cam member and said separating plate is actuated by arocking frame equipped with a second cam member and said vacuum cup ismounted on one arm of a bell crank of which the other arm is equippedwith a third cam member, and having a rotating cam formed with a lateralcam groove cooperating with said first mentioned cam member and a second lateral groove cooperating with said second cam member and aperipheral cam groove cooperating with said third cam member.

11. In a machine of the character described, a stationary frame, a pairof bed members transversely movable in said stationary frame, means forsimultaneously shifting said members equally to and from the median lineof the machine, and pairs of opposite and similar parts carried by saidmembers and together constituting means for supportiif a stack of latesand sheet-separating mec anism andp reciprocating slide-bar means fortransferring said plates longitudinally of the machine.

12. In a machine of the character described, a stationary frame, a camshaft journaled in said frame, a pair of laterally-adjustable bedmembers mounted on said stationary frame, and pairs of opposite similarcooperating parts mounted on said bed members, said airs including meansfor supporting a stac of plates and sheet-separating mechanism androtating cams having splined connection with said cam shaft andrespectively arranged to operate the parts of said supporting means andsaid sheet-separating mechanism.

13. In a machine of the character described, a stationary frame, a camshaft' journaled in said frame, a pair of laterally-adjustable bedmembers mounted on said stationaryl frame, and pairs of opposite similarcooperating parts mounted on said bed members, said pairs including apair of vertically-reciprocating supporting slides and a pair oflaterally oscillating separating plates and a pair of vacuum cupsarranged to cooperate successively with marginal portions of the sheetsbeing fed, and a pair of rotating cams having splined conllt) 4nectionwith said cam shaft and respectively coo eratively connected with saidsupporting reciprocatin sli es and separatingflates and vacuum cups. 14.In a machine o the character described and having formin mechanism andframe members formed wit a blank-supporting surface, reciprocating feedbars slidin ly mounted in said frame and having a p urality of feedpawls arranged the distance of one stroke a art, means for deliveringblanks on said I b ank sup orting surface in the path'of said feed pawthe distance between the center of the blanks at such point of deliveryand the center of the blanks at the forming mechanism being a givenwhole number of strokes a art, an actuating member having an invaria lestroke, and means for variab connecting said actuating member and saifeed bars to adjust the osition of said feed pawls with respect to thelank centers.

15. In a machine of the character described and having forming mechanismincluding a vertically reciprocating die and a horizontal mesma' plateVfor supporting the formed articles, a' g lblank-feeding mechanism" inhorizontal a lgnment with such plate includin means for removing formedarticles from said plate having a pair of slidingly-mounted pivotediingrs arranged to rock into position to enga e t e article 'during afeeding movement o lsuch blank-feedin mechanism and rock out of the pathof the ie of the forming mechanism during the return movementf of suchblank-feeding mechanism.

16. A machine of the character described according to claim 15 in whichsaid blankfeeding mechanism includes reciprocating feed bars arranged todeliver blanks laterally onto said (plate, a pair of blocks slidablymounted a jacent opposite sides of said plate, a pair of rocking fingersrespectively pivoted on said blocks, and links connected to said feedbars and also eccentrically connected said fingers.

EDWIN V. swANGaEi/i.

